Device for monitoring discharge processes in high-voltage power equipment

FIELD: measurement technique.

SUBSTANCE: invention refers to instrumentation technique with protection elements and can be used to record partial discharges incepted in insulation of high-voltage power equipment and to determine their level. Offered device for monitoring discharge processes in high-voltage power equipment contains four transmitting devices and receiving-analysing device. Each transmitting device includes piezoelectric sensor, pre-amplifier, radiomodule with antenna, detector of acoustic signal level, analog-to-digital converter, reference voltage unit, control unit and power supply unit. Receiving-analysing device contains transceiving module with radio antenna, unit for control of discharge process monitoring modes, unit for determination of data transmission channel number, event memory unit, unit for perceiving initial signs of discharge process, unit for comparing patterns of discharge process, library of discharge process patterns, unit for signal shape analysis and data display and signalisation unit.

EFFECT: improvement of quality of acoustic signal from partial discharges incepted in high-voltage equipment insulation analysis.

2 cl, 2 dwg

 

The invention relates to a measuring technique with elements of protection and can be used for registration of partial discharges occurring in the insulating power of high-voltage equipment, and determine their level.

Among the many parameters of the insulation of power high-voltage equipment, the characteristics of partial discharges (PD) are the most information about the risk of defects. One of the most effective ways to detect the CR equipment is acoustic method.

It is known device for controlling bit processes in high voltage power equipment containing multiple transmitting devices and receiving and analyzing device, and each transmitting device includes a piezoelectric transducer connected to a pre-amplifier, a radio with an antenna output and a power supply unit connected with all the blocks of the transmitting device and receiving and analyzing device comprises a receiving-transmitting module radio antenna input and the unit information display and alarm (Smekalov CENTURIES, Roshchupkin PPM, Tsvetaev S. Kaliev Acoustic Registrar bit processes with radio. - Journal of ELECTRO. Electrical engineering, electricity, electrical engineering, 2007, No. 2, p.34-37).

However, the known device does not provide the need for the CSO quality analysis of the acoustic signal, since it is not possible to identify the characteristic features (shape, frequency characteristics, their level) signal from the partial discharge occurring in the insulation of high voltage equipment. In addition, this device does not allow to determine the occurrence of the discharge.

The present invention is a device for controlling bit processes in high voltage power equipment, which allows to determine the form of the signal from the partial discharge occurring in the insulation of high voltage equipment, in order to reliably separate the signal from the discharge from the signal vibro mechanical process (vibration). This is necessary because when the service equipment is vibration together with the potential of having a bit of the process in isolation, since the presence of bit process a certain level of isolation is dangerous for the equipment.

The technical result of the invention is to improve the quality of analysis of the acoustic signal from the partial discharge occurring in the insulation of high voltage equipment.

The solution of the stated problem is achieved in that known device for controlling bit processes in high voltage power equipment containing multiple transmitting devices and receiving and analyzing device, the rich every transmitting device includes a piezoelectric sensor, coupled with a preamplifier, radio with antenna and power supply, coupled with all the blocks of the transmitting device and receiving and analyzing device comprises a receiving-transmitting module radio antenna and the display unit information and alarm systems, includes at least four transmitting devices, each of which further comprises a level detector acoustic signal, analog-to-digital Converter block of the reference voltage, the control unit and the memory unit, and receiving and analyzing device further comprises a control unit mode control bit process, the block defining a channel number information transfer, the memory block event block allocation initial indication bit process, the unit of measurement of mutual delays, the evaluation unit coordinate space of the discharge process, the unit of comparison images bit process, an image library bit process and the block shape analysis of the signal, and the sending unit, the control unit is connected to two-way communication with the analog-digital Converter, a memory unit and a radio module, the pre-amp output is connected to the second input of the analog-to-digital Converter, and through the detection level of the acoustic signal from the fourth input of the control unit, the output of the reference voltage is coupled to the third input of the analog-to-digital Converter, in receiving and analyzing the output device receiving and transmitting module connected to the inputs of the block defining a channel number of information transmission unit selection of the initial signs of a bit of the process and block compare bit images of process control inputs which are connected to the outputs of the control unit mode control bit process, the block number determination information channel is connected to the memory block event block allocation of the initial signs of a bit of the process is connected through series-connected unit of measurement of mutual delays and computing unit coordinate space bit process with the first input unit of the information display and alarm unit comparing the images bit process connected two-way communication with the image library bit process, and through the block shape analysis of the signal from the second input unit of the information display and alarm, in addition, the second output unit shape analysis of the signal is connected with the second input image library bit process, a block of memory of events connected two-way communication with the unit information display and alarm, and the fourth output control unit mode control bit process connected to the input of the receiving-transmitting module.

In addition, the power supply unit includes a coil and a is the production core, the multiplier AC condenser drive and control unit electronic switch connected in series, with the second output capacitor drive is connected to the output of the power supply via an electronic key, and the control input of the electronic key is connected to the output of the control unit of the electronic key.

Studies on patent and scientific and technical information sources showed that the proposed device is unknown and should not be explicitly studied the prior art, i.e. meets the criteria of "novelty" and "inventive step".

The proposed device is simple, constructive, it is easy to mount in place and it can be performed at any facility equipped with standard equipment produced by domestic or foreign industry.

Thus, the claimed device is available, and therefore, practically applicable.

In the drawings shows a device for controlling bit processes in high voltage power equipment.

Figure 1 shows the block diagram of the device for controlling bit processes in high voltage power equipment. Figure 2 presents the block diagram of the transmitting device.

Device for controlling bit processes in high voltage power equipment sod is RIT at least four of the transmitting device 1 and receiving and analyzing device 2 (see figure 1).

Each of the transmitting device 1 includes a piezoelectric sensor 3, the pre-amplifier 4, a detector 5 level of the acoustic signals, analog-to-digital Converter 6, block 7 of the reference voltage, the control unit 8, block 9 of the memory, the radio module 10 with the antenna 11 and block 12 power supply (see figure 2).

The power supply unit 12 is designed for the power transmitting device 1 by generating voltage under the influence of an external magnetic field, which is always present near high-voltage power equipment, and includes a coil 13 of the inductor core, multiplier 14 AC condenser drive 15, block 16 control electronic key and an electronic key 17.

The coil 13 of the inductor core unit 12 power supply converts a magnetic field, which is constantly present near high-voltage power equipment voltage. The multiplier 14 AC boosts and rectifies the output voltage of the coil 13 of the inductor, capacitor drive 15 is used for energy storage, and the block 16 controls the electronic key is designed to automatically activate the electronic key 17 when reaching required for operation of the voltage level.

Piezoceramic sensor 3 transmitting device 1 is designed to convert the ultrasonic waves caused by h is a partial discharge in an electrical signal. Pre-amplifier 4 amplifies this electrical signal and passes through the detector 5 level of the acoustic signal to the input of analog-to-digital Converter 6, which converts the received signal into digital form. Block 7 of the reference voltage generates the necessary voltage level for comparing it to an analog-to-digital Converter 6 with the received signal. The radio module 10 is designed for the broadcast data receiving and analysing device 2.

The control unit 8 is designed to encode the received signal and controls the analog-digital Converter 6, the memory unit 9 and the radio module 10.

Each of the transmitting devices 1 is rugged shielded case.

Receiving and analyzing device 2 receives, analyzes, stores and displays the received signal and its characteristics. It caters to all transmitting device 1 and includes: a receiving-transmitting module 18 with the radio antenna 19, block 20, the control mode of the control bit of the process unit 21 defining a channel number of information transmission unit 22 of the information display and alarm unit 23 of the memory of events, block 24 the initial signs of a bit of the process unit 25 measure the mutual delay unit 26 to calculate the coordinates designated bit process, block 27 comparison of images of the discharge is about process, library 28 images bit process and the block 29 analysis of the signal shape.

The principle of the proposed device to control the bit processes in high voltage power equipment is that the ultrasound accompanying spark or partial discharges, is transferred from the hard parts (shells, shells, insulators high-voltage power equipment) to sensitive piezoelectric sensor when in contact with these parts. This is due to the fact that bit process inside the high-voltage power equipment calls quickly ringing compression-tension environment, which causes the sound. Passing through the wall of the equipment, the sound waves are compression-tension turns into a wave spectrum, which fixes the piezoelectric transducer, the ultrasound is converted into an electric signal.

The device operates as follows.

In the process, high-voltage power equipment piezoceramic sensor 3 each of the transmitting device 1 converts the ultrasonic signal into an electrical signal, which then passes through the pre-amplifier 4 and the detector 5 level acoustic signal fed to the input of analog-to-digital Converter 6, which converts the received signals into digital form. Unit 7 supports the CSOs voltage transmitting device 1 generates the necessary voltage level for comparing it to an analog-to-digital Converter 6 with the received signal. The control unit 8 encodes the received signals and controls the analog-digital Converter 6, the memory unit 9 and the radio module 10.

The encoded signals from the output of the control unit 8 are received in the memory unit 9. After reaching the required, predetermined, number of reports, the control unit 8 generates the control signal for the radio module 10 and starts the data transfer by radio receiving and transmitting module 18 receiving and analyzing device 2.

Unit 9 memory allows you to quickly accumulate the signals and then slowly they send.

Receiving-transmitting module 18 receiving and analyzing device 2 (see figure 1) after receiving data sequentially transmits them to the input unit 21 to determine the channel number of information transmission unit 24 of the initial signs of a bit of process and unit 27 comparison of images based process of receiving and analyzing device 2.

Depending on the set program control and analysis of the results obtained bit processes in high voltage power equipment unit 20 of the control modes of the control bit process specifies various algorithms work units receiving and analyzing device 2.

There are three modes of receiving and analyzing device 2: monitoring mode, the locate mode, detection mode bit of processor is.

The operation of the device for controlling bit processes in high voltage power equipment in the monitoring mode involves transmission of data of all devices on the same frequency at any time. While receiving and analyzing device 2 receiving data from a transmitting device, analyzes and displays the results of the analysis. The recognition of a communication channel, and hence the transmitting device 1 receiving and analyzing device 2 produces by its number, which is transmitted together with an information signal. In this mode of receiving and analyzing device 2 are receiving and the transmitting module 18, unit 20 of the control modes of the control bit of the process unit 21 defining a channel number of the information signal, the block 23 to the memory of events and the block 22 information display and alarm.

When in locate mode transmission device 1 receives a command from block 20, the control mode of the control bit process to carry out measurements, the results of which remembers block 9 of the memory of the transmitting device, and then the radio module 10 reads the stored information and transmits it to different frequencies, each of which correspond to a particular transmitting device 1. In this mode, the process control and analysis of the obtained results is dejstvovany receiving-transmitting module 18, unit 20 of the control modes of the control bit process, block 24 the initial signs of a bit of the process unit 25 measure the mutual delay unit 26 to calculate the coordinates designated bit process and the block 22 information display and alarm receiving and analyzing device 2.

Program recognition bit processes allows you to quickly make a decision about the emergency shutdown of the equipment. In this mode of receiving and analyzing device are receiving and the transmitting module 18, unit 20 of the control modes of the control bit process, block 27 comparison of images bit process library 28 images bit process, block 29 analysis of the signal shape and the block 22 information display and alarm.

The device is used as follows.

On the surface of a controllable high-voltage unit is mounted conveying device 1, for example, using the built-in magnetic mount with rod (if the measurement is performed without stress) or manually. In this advance on the surface of the body, where the transmitting device 1, causing the grease to provide acoustic coupling of the sensor with the surface of the device.

On receiving and analyzing device 2 receives acoustic signals from each lane is giving the device 1. Analyzing the form of the received information signals, spectral characteristics, time and place of occurrence and comparing them with typical information signal, which corresponds to the object and the installation location of the transmitting device 1, decide on further action until the emergency shutdown equipment.

The proposed device for controlling bit processes in high voltage power equipment provides quality analysis of the acoustic signal from the partial discharge occurring in the insulation of high voltage equipment, as it allows you to effectively separate the acoustic signals bit processes from vibro mechanical processes, as well as to determine the location of defects in the equipment in which the area of occurrence of partial discharge encased under a high potential. The definition of designated bit development process is extremely important when conducting diagnostic testing of high voltage equipment.

To use the proposed device can be used as a process for Autonomous system monitoring and operational control of high voltage power equipment without (with) off(-em), with installation of the transmitting device insulating rod (manually). Also enabled is but the application of the proposed device to the grounded parts of the high-voltage equipment, for example, the elements of complete switchgear gas-insulated (GIS), the limit, the couplings of cable lines, etc.

1. Device for controlling bit processes in high voltage power equipment containing multiple transmitting devices and receiving and analyzing device, and each transmitting device includes a piezoelectric sensor, connected to a preamplifier, radio with antenna and power supply, coupled with all the blocks of the transmitting device and receiving and analyzing device comprises a receiving-transmitting module radio antenna and the display unit information and signaling, characterized in that it includes at least four transmitting devices, each of which further comprises a level detector acoustic signal, analog-to-digital Converter block of the reference voltage, the control unit and memory block, and receiving and analyzing device further comprises a control unit mode control bit process, the block defining a channel number information transfer, the memory block event block allocation of the initial signs of a bit of the process, the unit of measurement of mutual delays, the evaluation unit coordinate space of the discharge process, the unit of comparison images bit process, an image library time is adnego process and the unit of analysis waveform, moreover, in the sending unit, the control unit is connected to two-way communication with the analog-digital Converter, a memory unit and a radio module, the pre-amp output is connected to the second input of the analog-to-digital Converter, and through the detection level of the acoustic signal from the fourth input of the control unit, the output unit of the reference voltage is connected to the third input of the analog-to-digital Converter, receiving and analyzing the output device receiving and transmitting module connected to the inputs of the block defining a channel number of information transmission unit selection of the initial signs of a bit of the process and block compare bit images of process control inputs which are connected to the outputs of control unit control modes bit process, the block number determination information channel is connected to the memory block event block allocation of the initial signs of a bit of the process is connected through series-connected unit of measurement of mutual delays and computing unit coordinate space bit process with the first input unit of the information display and alarm unit comparing the images bit process connected two-way communication with the image library bit process, and through the block shape analysis of the signal with the second input display unit is of information and signaling, in addition, the second output unit shape analysis of the signal is connected with the second input image library bit process, a block of memory of events connected two-way communication with the unit information display and alarm, and the fourth output control unit mode control bit process connected to the input of the receiving-transmitting module.

2. Device for controlling bit processes in high voltage power equipment according to claim 1, characterized in that the power supply contains an inductor core, multiplier AC condenser drive and control unit electronic switch connected in series, with the second output capacitor drive is connected to the output of the power supply via an electronic key, and the control input of the electronic key is connected to the output of the control unit of the electronic key.



 

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